A common challenge of injection molds is the difficulty to achieve and maintain a uniform wall thickness of the molded part while overcoming and compensating for various injection molding processing conditions. Prior art injection molds typically have a core versus cavity locking system, with wedges having various clamp angles such as 7° to 20° angles. While the clamping force of the injection press holds the mold closed during injection, injection forces sometimes overcome the clamping force, causing the mold to breathe at the parting line. As an example, a breathing gap of 0.001″-0.007″ at the parting line, combined with angles of 7°-20° on wedges, produces gaps of 0.0009″-0.0024″ between core and cavity wedges, resulting in loss of concentricity where one side of the mold half shifts out of center to the opposing side and causes inconsistent wall thickness of the molded part. A typical procedure to restore concentricity is to shim the wedges; this method however is time consuming and offers only temporary results since the processing conditions that caused the core verses cavity shifting is continuously present. A solution to counter this problem is to use smaller angles on wedges (3° or 1° or less), but such small angle makes for difficult control of thermal expansions and tends to cause the wedges to gall and/or seize. Furthermore the tolerances required to build a mold and maintain the same mold increases which results in more cost.
Therefore, existing locking systems pose an ongoing challenge to remove the floating effect caused by high injection pressures. A solution is desired, which allows the locking system to constantly self-adjust in order to maintain concentricity, while allowing control of thermal expansions and preventing galling of the wedges ans.